Walls constructed of concrete blocks or bricks are frequently finished with materials such as stucco, paneling, siding, or similar materials. These finishing materials are installed to enhance the attractiveness of the wall.
To provide electrical services to the wall, electrical boxes are commonly secured to the wall prior to installing the finishing layer. Prior to installing the finishing layer, the installer typically breaks a hole in a block at the desired location for an electrical box. The hole, typically made with a hammer and chisel, is usually somewhat larger than the box. Furring strips are then typically secured to the surface of the block wall to provide a brace for accepting the fasteners of a standard electrical box. The electrical box is then placed within the furring strips and secured at the desired depth within the wall to accommodate the finishing layer that will later be installed thereon. The electrical box is therefore mounted in a position where its front edge will be even with the surface of the installed finishing layer. Since numerous finishing materials are available, and they are available in different thicknesses, it is a very cumbersome and difficult task to install the electrical box with a great degree of certainty that it will be approximately even with the eventual finished layer surface. Standard electrical boxes typically have nails or screws set an angle to the front edge of the box and they typically tend to shift the box as the fasteners are hammered or screwed into the furring strips. To seal against drafts, the oversize hole is typically filled in by blowing pressurized foam, such as polyurethane foam, into the space between the box and surrounding block surface to seal the space between the box and the block. After the foam has cured, portions of it typically extend outwards of the block wall and from the base of the electrical box.
This prior art method of installing an electrical device is illustrated in FIGS. 12 and 13. FIG. 12 depicts in exploded relationship an oversize hole 200 broken in the block wall 202, two furring strips 204 secured to the wall by fasteners 206, a prior art electrical box 208, a duplex receptacle 210, and a faceplate 212. The furring strips 204 are secured to the wall, the prior art electrical box 208 is secured to one of the furring strips 204 by a fastener 214, and a duplex receptacle 210 and a faceplate 212 are in alignment with the prior art electrical box 208. FIG. 13 depicts a completed installation of a prior art electrical box 208 to a block wall 202 including the furring strips 204 secured to the wall 202, the electrical box 208 secured to one of the furring strips 204, and cured polyurethane foam 216 that has been used to fill the hole. With reference to FIGS. 12 and 13, it should be apparent that this prior art method of providing an electrical box 208 on a block wall 202 is a tedious, labor intensive, time-consuming task that does not always result in the front edge 218 (see FIG. 12) of the electrical box being level with the eventual finished wall surface. In this prior art method of installing an electrical box to a block wall, it is difficult to get the proper offset from the anticipated surface of the later installed finished layer, as the prior art box is mainly intended for installation on framed walls, and the fasteners that come with the box are not positioned and angled to create a desired offset. The installer must therefore estimate the desired position of the electrical box to make it even with the finished wall.
What is needed therefore is a device that reduces the time and effort involved in installing an electrical box in a concrete block wall, brick wall, or similar surface, and enables the installer to easily mount the box at the desired offset from the wall's outer surface.